Detailing The Neuroretinal Rim Tissue For Glaucoma.

Purpose. Twenty percent of all law suits filed against Eye Care Practitioners (ECP) are
related to the misdiagnosis of glaucoma, which is currently the highest amongst all other ocular anomalies. Diagnosis of glaucoma is based upon a multitude of techniques including information provided by a dilated non-contact fundus examination, Heidelberg Retinal Tomographer (HRT), Glaucoma Diagnosis (GDx), Optical Coherence Tomography (OCT) and scanning laser ophthalmoscope (SLO). All methods mentioned provide objective quantitative information of the optic nerve head; however, many ECP do not have access to this equipment. For the average ECP, diagnosis of glaucoma is primarily based upon a subjective dilated non-contact fundus examination with a cup-to-disc ratio (C/D) as the only quantitative information available. Assessing the C/D ratio has inherent flaws including overlooking the placement of the cup, judgment based upon color and concentration of the cup as opposed to the neuroretinal rim tissue which is where loss occurs during the process of glaucoma. The need for a standardized objective method to evaluate the neuroretinal
rim tissue is required for the proper diagnosis of a suspicious or glaucomatous optic nerve during a dilated non-contact fundus examination. Methods. Fundus photography has been obtained from subjects in order to describe proper evaluation of the rim tissue based upon a grid format. A literature review was conducted to
support our findings. Results. A measurement system is explained within the article taking into account optic nerve head size and appropriate conversion factors.
Conclusions. A grid format for measurement of the optic nerve.